Ammunition



Patented Feb. 8, 1944 AliiMUNITION Gordon M. Calhoun, Fairfleld, Conn., and Peter B. Rutherford, Herkimer N. Y., assignors to Remington Arms Company, Inc., a corporation of Delaware Application July 1, 1941, Serial No. 400,606

' 6 Claims. (01.102-38) component is placed in the shell in a moist condition.

In the manufacture of rimfire cartridges as universally practiced in this country, the' cartridge shell is provided with a hollow rim, and the priming composition is prepared in a moist pasty condition by admixture with a phlegmatizing liquid and separated into pellets, one of which is dropped into each empty shell. The material of the pellet is then spun outward to its final position partly into the hollow rim, after which the mixture is dried. Drying may be accomplished in open air, but this requires several days, the time depending upon atmospheric humidity. Frequently artificial heat is used, but such accelerated drying requires the use of expensive equipment. After drying, there is necessarily considerable handling of the shells in large lots as they are arranged to receive the charge of powder and the bullet which completes a cartridge. It being impracticable in quantity production to get all of the mixture into the hollow rim and to leave other interior surface of the shell entirely clean, grains or fragments of the dry and percussion sensitive mixture may be dislodged and fall out of the shell, and, as the shells are moved about in handling, may be exploded by friction ,or impact against the shells or containing bins or hoppers. With some types of priming mixtures, the explosion of a few grains of a mixture thus dislodged is a disturbance of sufficient intensity to explode the mixtures in place in contiguous shells, which in turn explode or scatter others with undesirable results.

Thedrying of the priming mixture prior to loading has hitherto been considered essential. Wet priming mixture is not sensitive to percussion, and further, if a shell containing a wet mixture is loaded with propellant powder, the moisture of the mixture is transferred to the powder with a detrimental effect upon is ballistic properties.

The present invention contemplates the discovery of a method by which the drying step and the handling of empty shells containing dry priming mixture is wholly eliminated and it is made possible to complete cartridges by the assembly of powder and bullet while the priming mixture is still moist and inert. This novel object is accomplished by the use of desiccants in such quantities and as of such properties that they withdraw the moisture from the priming mixture and retain it, leaving the priming mixture in the desired percussion sensitive condition and the powder in the same condition in which it was loaded, Such. desiccants may be used in various ways. Typical cartridges are illustrated in the drawing, in which Fig. 1 is a sectional elevation of a rimfire cartridge, including a desiccant used in accordance with a preferred form of the present invention;

Fig. 2 is a sectional elevation of a rimfire cartridge, showing a modification in the use of the desiccant; and

Fig. 3 is a sectional elevation of a rimfire cartridge, showing afurther modification.

Referring particularly to Fig. 1, the cartridge comprises the usual shell in having a hollow rim which contains the priming mixture H upon which is placed a powder charge l2. Within the forward end of the shell I0 is a bullet H3. The desiccant i5 is placed above the powder charge and preferably separated therefrom by a thin cardboard wad IS. The desiccant may be in powder or granular form or in the form of precompressed Pellets of any desired size.

In the form of the invention shown in Fig, 2, thedesiccant is carried by an absorbent body or wad 20, preferably placed above the powder charge. The absorbent body may be cardboard, asbestos, rayon waste, regenerated cellulose sponge, or other loosely compacted body. which is impregnated with the desiccant in any desired manner, such as dipping in a solution or suspension thereof and subsequently evaporating the fluid, leaving the dry desiccant distributed throughout the porous body.

In the form of the invention illustrated in Fig. 3, the desiccant H is mixed with the powder charge. It attracts and retains the moisture of the priming mixture, leaving both primer and powder charge in the desired dry condition.

Both chemical and mechanical desiccants may be used, Such chemical desiccants as calcium oxide, calcium sulphate, calcium chloride, etc., function for this purpose in a well-known manner. In place of or in addition to such chemical desiccants, there may be used desiccants of the type of activated alumina, which adsorbs the fluid upon its surface. The use of halogen compounds is undesirable due to their corrosive action upon the steel of gun barrels.

The use of desiccants is not limited to any particular priming mixture, it having been found possible to use suitable desiccants for the Purpose of drying any mixture susceptible to wet loading in rimfire or center-firecartridges or shot shells. Neither is the use of any particular powder essential, the desiccants withdrawing and retaining moisture in the presence of many difl'erent black, semi-smokeless, and single 'and multibase smokeless powders.

The use of desiccants as a means for removin moisture from ammunition priming compositions while in place in a shell or a primer cup being broadly new, the appended claims are to be broadly construed.

What is claimed is:

1. An assembled cartridge comprising a shell having a hollow rim, a priming composition'in said rim, a propellant powder charge within the body of said shell, and a desiccating material superposed upon said powder charge.

2. A cartridge comprising a shell, a priming mixture, 2. propellant powder charge, a desiccating material, and a projectile, all held in place in said shell. I

3. A cartridge comprising a shell containing a priming mixture, a powder charge, and a desiccant selected from the group consisting of calcium oxide,-calcium sulphate, calcium chloride and alumina.

4. In the loading of firearms cartridges, the method which comprises placing in a cartridge shell a moist priming mixture, 9. powder charge, and a desiccating material; and closing said shell to complete said cartridge, the moisture of said priming mixture-being subsequently transferred to said desiccating material, leaving said priming mixture in a dry. percussion sensitive condition. I

5. In the loading of firearms cartridges, the method which comprises placing in a cartridge shell a moist priming mixture, superposlng upon said moist priming mixture a. charge or powder admixed with a desiccating material, and closing said shell to complete said cartridge, the moisture of said priming mixture being subsequently transferred to said desiccating material, leaving said priming mixture in a dry, percussion sensitive condition.

6. In the loading of firearms cartridges, the method which comprises placing a moist priming mixture in a shell, superposing a charge oi! powder on said priming mixture, superposing a desiccatin'g material upon said powder charge, and closing said shell to complete said cartridge, the moisture of said priming mixture being subsequently transferred to said desiccating ma- GORDON M. CALHOUN. PETER B. RUTHERFORD. 

